1. Field of the Invention
This invention relates to continuous three phase absorption systems which utilize the heats of absorption as heat sources for heat pump systems and the heats of desorption to pressurize gaseous refrigerants for cooling and/or refrigeration systems.
2. Description of the Prior Art
Absorption systems using solid absorbents for heating and cooling have been designed to be driven by relatively low temperature heat sources. The two phase absorption system in U.S. Pat. Ser. No. 4,055,962 utilizes the heat of absorption and desorption for hydrogen gas and several exotic metals capable of chemically forming hydrides, LaNi.sub.4 Cu, FeTi, etc. This system uses a plurality of reactors to make an intermittent process into a continuous system. A three phase intermittent type of absorption system was recently disclosed in U.S. Pat. Ser. No. 4,205,531 which uses heats of vaporization and condensation for condensible bipolar gases and heats of formation for compounds formed from these gases when absorbed on porous sodium sulfide, Na.sub.2 S, and other chemically related solids.
A disadvantage of the hydride absorption system is the high cost of the exotic absorbent metals required. The three phase system as described in U.S. Pat. Ser. No. 4,205,531 is intermittent and therefore, if long term cooling and/or heating is to be achieved, either enormous quantities of absorbing solids must be provided for storage or a backup cooling and heating system is required while the absorption system is being recharged. However, both of these systems have high thermal efficiencies compared to conventional heating and cooling systems that use mechanical compressors.